Treatment of organic waste products

ABSTRACT

A process for the treatment of human organic waste products or the like whereby harmless inoffensive gases are produced. In the process, the organic waste products are combined with water to form a fine particle slurry. The slurry is introduced below the surface of a body of suitable molten metal contained in a primary combustion vessel to produce carbon dioxide, water vapor and other gases. The carbon dioxide, water vapor and other gases are introduced into a heated secondary combustion vessel to further oxidize the gases and produce harmless, inoffensive gases which may be vented to the atmosphere.

United States Patent Patterson [54] TREATMENT OF ORGANIC WASTE PRODUCTS221 Filed: Apr. 22, 1971 211 App]. No.: 136,435

[52] US. Cl ..210/60, 23/2, 110/8, 203/100, 210/61, 210/63, 210/71 [51Int. Cl ..C02c 5/04 [58] FieldofSearch ..210/12,63,71,60,61; 203/100 DC;110/8; 23/2 [5 6] References Cited UNITED STATES PATENTS 3,306,2362/1967 Campbell "110/8 R June 6, 1972 3,527,178 9/1970 Southwick..ll0/8E 2,976,224 3/1961 Gilliland ..203/10O DC Primary ExaminerMichaelRogers Attorney-Dunlap, Laney, Hessin & Dougherty ABSTRACT A process forthe treatment of human organic waste products or the like wherebyharmless inoffensive gases are produced. In the process, the organicwaste products are combined with water to form a fine particle slurry.The slurry is introduced below the surface of a body of suitable moltenmetal contained in a primary combustion vessel to produce carbondioxide, water vapor and other gases. The carbon dioxide, water vaporand other gases are introduced into a heated secondary combustion vesselto further oxidize the gases and produce harmless, inoffensive gaseswhich may be vented to the atmosphere.

9 Claims, 3 Drawing Figures 1. Field of the Invention This inventionrelates to a process for converting human waste products or the likeinto harmless inoffensive gases.

2. Description of the Prior Art Many attempts have been made in the pastto treat human waste products and the like before returning theseproducts to the environment. Most of the commonly accepted processespresently used involve the addition of various chemical compounds to thewaste products to react with and to form other compounds which are notconsidered to be pollutants to the environment. Generally theseprocesses are dependent upon the operator to add the necessary chemicalsand therefore are subject to neglect resulting in the discharge ofpollutants.

Another common method of disposing of organic waste products is tocombine these products with water and spray the resulting slurry in afine mist into a combustion chamber through a nozzle device where thewaste products are oxidized. A disadvantage inherent in this method isthat particles of waste material tend to stop up the nozzle device atfrequent intervals requiring the process to be stopped while the nozzledevice is disassembled and cleaned to remove the offending particles.Another disadvantage exhibited by this method is that waste productparticles may be passed through the combustion chamber before thechamber has reached a temperature high enough to assure adequateoxidation of the waste products.

In certain applications, it is not convenient or economical to providelarge storage reservoirs to contain waste products. One such applicationis on board a vessel in waters where overboard discharge of wasteproducts in an untreated state is prohibited. Another such applicationis at a temporary construction site where construction of largepermanent waste treatment facilities is not feasible. Yet another such'application is in extremely low temperature climates where soil andstreams are frozen to depths which prevent the utilization of commonsewage disposal methods.

SUMMARY OF THE INVENTION The present invention is directed to a processfor converting human organic waste products or'the like into harmlessinoffensive gases wherein the waste products are combined with aquantity of water to form a slurry comprised of water and fine particlesof waste products. The slurry is introduced below the surface of a bodyof molten metal so that carbon dioxide, water vapor and other gases areformed therefrom. The carbon dioxide, water vapor and other gases arethen removed from the body of molten metal.

It is, therefore, an object of the present invention to provide aprocess for the conversion of human waste products or the like intoharmless inoffensive gases.

Another object of the present invention is to provide a process for theconversion of human waste products or the like into harmless inoffensivegases which process is suitable for use aboard a vessel, at temporarylocations or in extremely low temperature climates.

A further object of the present invention is to provide a process forthe conversion of human waste products or the like into harmlessinoffensive gases which may be carried out in apparatus of small size.

Another object of the present invention is to provide a process for theconversion of human waste products or the like into harmless inoffensivegases which process is efficient and economical.

Other objects and advantages of the present invention will be evidentfrom the following detailed description when read in conjunction withthe accompanying drawings.

BRIEF DESCRIPTION OF THE DRA\VINGS FIG. 1 is a diagrammatical view ofthe combustion vessels of the present invention.

FIG. 2 is a diagrammatical view of another embodiment of combustionvessels of the present invention.

FIG. 3 is a diagrammatical view of one form of the process of thepresent invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings,and particularly to FIG. 1, the reference character 10 generallydesignates the apparatus of the present invention. In the preferredembodiment, the apparatus 10 includes a closed primary combustion vessel11, containing a suitable molten metal bath 12 in the lower portionthereof. A suitable metal for use in the molten metal bath is lead whichis maintained within a preferred temperature range of 620 to 900 F. Aline 14 extends into the lower portion of the molten metal bath throughwhich a fine particle slurry comprised of organic waste products andwater are introduced into the lower portion of the molten metal bath.Another line 16 extends into the lower portion of the molten metal baththrough which air may be introduced into the lower portion of the moltenmetal bath from outside the vessel 11.

A conduit 18 interconnects the upper portion of the primary combustionvessel 11 and the upper portion of a closed secondary combustion vessel20. A line 22 extends from the lower portion of the secondary combustionvessel upwardly therethrough to connect with a conduit 24 external tothe second combustion vessel. The second combustion vessel 20 ismaintained within a preferred temperature range of l,450 to 1,700" F.

OPERATION OF THE PREFERRED EMBODIMENT In operation, a fine particleslurry comprised of organic waste products and water is introduced intothe lower portion of the molten metal bath 12 through line 14. Uponcontact with the molten metal bath, the water in the fine particleslurry is immediately vaporized, forming bubbles in the molten metalbath which travel upwardly therethrough. The bubbles of water vaporcarry particles of the organic waste products upward through the moltenmetal bath, dispersing the fine particles of organic waste productsthroughout the molten metal bath and exposing them to the elevatedtemperature thereof. The waste products are predominantly hydrocarboncompounds. At the high temperature of the molten metal bath, the fineparticles of waste products are ionized and will be readily oxidized.Depending upon the amount of water combined with the waste products inthe slurry, it may be desirable to introduce air into the molten metalbath through the line 16 which will bubble upwardly through the moltenmetal bath along with the water vapor and fine particles of wasteproducts to provide additional oxygen for the oxidation process takingplace in the vessel 11.

Upon contact with the molten metal bath 12, carbon from the wasteproducts is ionized and readily reacts with the oxygen and the watervapor to form hydrogen and other gases, including carbon dioxide. Thesereactions may be written as follows:

The waste products also contain a considerable amount of sulphur whichis readily oxidized at the elevated temperature of the molten bath.Sulphur entering the molten metal bath reacts with the water vapor toform hydrogen and sulphur dioxide. This reaction may be written asfollows:

Those solid particles of waste material and salts contained in the waterwhich are not vaporized will float to the top of the molten metal bath12 to form a layer of slag which is removed from the vessel 11periodically. It should be noted that the formation of slag on top ofthe metal bath will not cause a stop- 1 page of the process therebypermitting the scheduling of slag removal at convenient times when theapparatus is idle.

The carbon dioxide, hydrogen, water vapor and other gases formed in thereaction within the molten metal bath 12 pass upwardly through themolten metal bath 12 and out of the primary combustion vessel 1 1through conduit 18. The gases pass through conduit 18 to the secondarycombustion vessel 20 wherein the gases are heated to further oxidize theother gases and produce harmless inoffensive gases which may then bevented to the atmosphere without polluting effect. These gases are thenremoved from the secondary combustion vessel through line 22 to conduit24.

It should be noted that no flow of waste products can be obtained untilsufficient heat has been added to the primary combustion vessel 1 l torender the metal bath l2 molten. This is a safety feature of the processof the present invention which prevents untreated waste products frompassing through the apparatus 10.

Again, depending onthe amounts of water combined with the waterproducts, it may be desirable to introduce additional air into thesecond combustion vessel 20 to provide additional oxygen to complete theoxidation of any partially oxidized gases passing therethrough.

FIG. 3 diagrammatically illustrates the overall process of the presentinvention. A source of organic waste products 26 supplies waste productsto a macerator 28 of conventional design through conduit 30. Water isalso supplied to the macerator 28 through the conduit 30 along with thewaste products. The water is used to flush the waste products alongthrough the conduit 30 from the source of waste products 26. A fineparticle slurry is formed in the macerator 28 from the waste productsand the water contained therein. The fine particle slurry is removedfrom the macerator 28 and pumped through conduit 32 by pump 34 to theapparatus 10. The slurry is processed in the primary combustion vessel11 and the secondary combustion vessel 20 as described above, and thegases formed during this process are removed from the secondarycombustion chamber 20 through conduit 24.

A two-way valve 36 is installed in the conduit 24 and allows the gasesbeing conducted therethrough' to be selectively vented to the atmosphereor, alternately, conducted to a condensor 38. The condensor 38 is ofconventional design and may be conveniently cooled by water. In thecondensor 38, the water vapor is condensed from the gases and the liquidwater is conducted through conduit 40 to water reservoir 42. The othergases are also conducted through the conduit 40 to the water reservoir42 and are vented to the atmosphere through conduit 44.

The water contained in the water reservoir 42 is conducted therefromthrough conduit 46to the source of waste products 26 to be recycledthrough the process.

The source of waste products 26 may be a flush-type toilet ofconventional design or a storage tank connected thereto.

EMBODIMENT OF FIG. 2

FIG. 2 illustrates an alternate embodiment of the apparatus of thepresent invention which is generally designated by the referencecharacter a wherein the secondary combustion vessel 48 contains a moltenmetal bath 50 of a suitable metal such as lead. When the molten metalbath 50 is lead, it is maintained within a preferred temperature rangeof 620 to 900 F.

The gases conducted from the primary combustion vessel ll through theconduit 18 are introduced beneath the surface of the molten metal bath50 through line 52. Depending on the amount of water combined with thewaste products, it may be desirable to introduce air beneath the surfaceof the molten metal bath through line 54. The gases bubble up throughthe molten metal bath 50 with the gases readily reacting with the watervapor and the oxygen from the air if air is being introduced, tocomplete the oxidation process of the gases. The gases are then removedfrom the secondary combustion vessel through conduit 24 and may beprocessed further as described above and illustrated in FIG. 3.

What is claimed is: l. A process for converting human organic wasteproducts or the like into harmless inoffensive gases comprising thesteps of:

combining a quantity of water with the waste products so that a slurryis formed comprising water and fine particles of the waste products;introducing the slurry beneath the surface of a first body of moltenmetal so that carbon dioxide, water vapor and other gases are formed;and

removing the carbon dioxide, water vapor and of the gases from the bodyof molten metal.

2. A process as defined in claim 1 including the additional steps ofsimultaneously introducing air beneath the surface of the first body ofmolten metal to provide additional oxygen to oxidize the fine particlesof waste material.

3. A process as defined in claim 1 including the additional steps of;

introducing the carbon dioxide, water vapor and other gases into avessel to oxidize the other gases so that additional carbon dioxide,water vapor and other gases are formed therefrom; and

removing the carbon dioxide, water vapor and other gases from thevessel.

4. A process as defined in claim 3 including the additional step ofsimultaneously introducing air into he vessel to provide additionaloxygen for the oxidation of the other gases.

5. A process as defined in claim 3 including the step of condensing thewater vapor removed from the vessel.

6. A process as defined in claim 5 including the step of recycling thecondensed water for combination with additional waste products.

7. A process as defined in claim 1 including the steps of:

introducing the carbon dioxide, water vapor and other gases beneath thesurface of a second body of molten metal to form additional carbondioxide, water vapor and other gases; and

removing the additional carbon dioxide, water vapor and other gases fromthe second body of molten metal.

8. A process as defined in claim 7 including the step of simultaneouslyintroducing air beneath the surface of the first body of molten metal toprovide oxygen to react with the gases introduced therein.

9. A process as defined in claim 7 including the step of simultaneouslyintroducing air beneath the surface of the second body of molten metalto provide oxygen to react with the other gases introduced therein.

2. A process as defined in claim 1 including the additional steps ofsimultaneously introducing air beneath the surface of the first body ofmolten metal to provide additional oxygen to oxidize the fine particlesof waste material.
 3. A process as defined in claim 1 including theadditional steps of; introducing the carbon dioxide, water vapor andother gases into a vessel to oxidize the other gases so that additionalcarbon dioxide, water vapor and other gases are formed therefrom; andremoving the carbon dioxide, water vapor and other gases from thevessel.
 4. A process as defined in claim 3 including the additional stepof simultaneously introducing air into he vessel to provide additionaloxygen for the oxidation of the other gases.
 5. A process as defined inclaim 3 including the step of condensing the water vapor removed fromthe vessel.
 6. A process as defined in claim 5 including the step ofrecycling the condensed water for combination with additional wasteproducts.
 7. A process as defined in claim 1 including the steps of:introducing the carbon dioxide, water vapor and other gases beneath thesurface of a second body of molten metal to form additional carbondioxide, water vapor and other gases; and removing the additional carbondioxide, water vapor and other gases from the second body of moltenmetal.
 8. A process as defined in claim 7 including the step ofsimultaneously introducing air beneath the surface of the first body ofmolten metal to provide oxygen to react with the gases introducedtherein.
 9. A process as defined in claim 7 including the step ofsimultaneously introducing air beneath the surface of the second body ofmolten metal to provide oxygen to react with the other gases introducedtherein.